It is often useful to be able to stack containers for transportation or storage. This is particularly so with large, industrial sized containers, for example 5 gallon pails.
The weight of a large container, when filled, is quite significant and where filled containers are to be stacked, the lid design must be capable of taking the load of the containers stacked above and transmitting it to the containers below. The difficulties of designing a suitable container lid for this purpose are augmented where the container has a membrane sealed across its mouth before the lid is installed. The lid cannot be permitted to damage the membrane in any way
The present invention is concerned with the provision of a container lid for large, stacking containers sealed with membranes.